Device and method for enhanced visualization of the small intestine

ABSTRACT

A device for distending a body lumen for enhanced visualization with a capsule endoscope that includes a camera lens includes an attachment element configured to attach to the capsule endoscope and a plurality of struts extending from the attachment element and meeting at an apex. The plurality of struts are configured to extend both axially and radially away from the camera lens so as to form a frame therearound.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/376,816, filed Aug. 18, 2016 and titled “DEVICE AND METHOD FORENHANCED VISUALIZATION OF THE SMALL INTESTINE,” the entirety of which isincorporated by reference herein.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BACKGROUND

Endoscopy, the study or examination of the inside of the body, is acommon procedure performed by gastroenterologists inside of thegastrointestinal (GI) tract. It is typically accomplished with long,slender endoscopes, either rigid or flexible.

For typical endoscopy, visualization of the GI tract is significantlyenhanced by insufflation, i.e., the release of pressurized gas (air orCO2). Because collapsed tissue inhibits visualization, insufflation isused to expand or distend the GI tract so that it can be fullyvisualized. Without such inflation, endoscopy moves through only aportion of an often-flattened lumen, failing to image significant partsof the lumen. As a result, incomplete evaluation of the bowel is commonwhen insufflation is not used. Luminal distention is therefore oftencritical for endoscopy for better visualization, detection, and theefficacy of the entire examination. FIGS. 1A-1E shows the advantages ofinsufflation distention during a typical endoscopy procedure. FIG. 1Ashows the intestine in its deflated state with no markers visible. FIG.1B shows that with just 50 mL of insufflation, 4 of the 9 markes becomevissible. FIG. 1C shows insufflation at 200 mL. FIG. 1D showsinsufflation at 450 mL. FIG. 1E shows the intestine fully inflated at1500 mL.

However, traditional endoscopy is invasive, usually requires anesthesia,and can be very difficult to move through the small intestine. Recently,there has been commercial success for a distinctly new class of devicesknown as capsule endoscopes (CE) (including pill cameras, pillcams,wireless capsule endoscopes, or video capsule endoscopes (VCE)). Capsuleendoscopies have been revolutionary for gastroenterology, enablingdiagnostic procedures that are non-invasive, do not require anesthesia,and provide visualization of anatomies that were previously poorlyinterrogated, including the small intestine. With capsule endoscopy,manufacturers have gone to great lengths to improve visualization,adding ever-more cameras, side-view cameras, rotating cameras, cameraswith a widening field of view, or finer resolution, an increasedquantity of more powerful LEDs, faster data transfer rates, andradically higher frame rates. However, none of these improvements aremeaningful or helpful if the lumen is flattened and/or covers the lens.

For capsule endoscopy, luminal expansion techniques are currently notavailable. As such, the procedure's visualization, and thus its entirediagnostic yield and efficacy, is significantly limited. FIGS. 2A-2Dshow exemplary instances in which the field of view with a capsuleendoscope can be obscured. FIG. 2A, for example, shows the lumen 200collapsed around the capsule endoscope 222. FIG. 2B shows scope 222oriented towards a fold in the wall of the lumen 200. FIG. 2C showslocalized immersive mucosal contact of the lumen 220 with the scope 222.Finally, FIG. 2D shows deep folds in the lumen 200, which can hindervisualization with the scope 222. These exemplary scenarios can resultin occlusion of the lens, a view of only the closed tissue, and/or animpartial view caused by blood, debris, or tissue interfering with thelens. As a result, typical capsule endoscope diagnostic efficacy ratesare sub-par, estimated at only around 50%. Despite patient experienceadvantages relative to traditional endoscopic devices, these suboptimalrates have prevented the devices from reaching their potential.

Studies have been performed with capsule endoscopes that release gasinto the gastrointestinal tract for insufflation, and the results showradically improved visualization. Gas release in such studies wasaccomplished, for example, through the release of pressurized air or asthe by-product of a chemical reaction. However, storing and methodicallyreleasing pressurized air aboard a capsule in the gastrointestinal tractis problematic. Excessive localized gas release can cause patientdiscomfort. Chemical reactions struggle with heat, biocompatibility,foaming and bubbles, longevity, and adequate volume.

Capsule endoscopes including built-in radial extensions have beenproposed as a means of making the device more lumen-centric to improveimaging, but these structures do not serve to adequately tent smallintestine tissue, as the small intestine tissue is very thin, soft, andcompliant and tends to fold over onto the lens of the scope.

A device for use with a capsule endoscope that addresses some or all ofthese problems is thus desired.

SUMMARY OF THE DISCLOSURE

In general, in one embodiment, a device for distending a body lumen forenhanced visualization with a capsule endoscope that includes a cameralens includes an attachment element configured to attach to the capsuleendoscope and a plurality of struts extending from the attachmentelement and meeting at an apex. The plurality of struts are configuredto extend both axially and radially away from the camera lens so as toform a frame therearound with the apex positioned a set axial distanceaway from the camera lens.

This and other embodiments can include one or more of the followingfeatures. The attachment element can be an annular ring. The attachmentelement can be configured to attach to the capsule endoscope throughfriction fit, adhesive, or clamping. The frame can include a shoulderthat is positioned a maximum radial distance away from the capsulescope. The shoulder can be axially offset away from the camera lens. Adistance between the shoulder and the apex can be between 10 mm and 30mm. A diameter of the frame at the shoulder can be between 20 mm and 40mm. The frame can include a tapered tip. An angle of the taper can bebetween 30° and 60°. The set axial distance can be between 25 mm and 45mm. The struts of the plurality of struts can be separated by 30° to120°. There can be between 4 and 6 struts in the plurality of struts.Each of the plurality of struts can be self-expandable. Each of theplurality of struts can be formed of a shape memory material. The framecan include a biodegradable portion.

In general, in one embodiment, a device for visualization of a bodylumen includes a capsule endoscope with a camera lens and a plurality ofstruts extending from the capsule endoscope and meeting at an apex. Theplurality of struts extend both axially and radially away from thecamera lens so as to form a frame therearound with the apex positioned aset axial distance away from the camera lens.

This and other embodiments can include one or more of the followingfeatures. The frame can include a shoulder that is positioned a maximumradial distance away from the capsule endoscope. The shoulder can beaxially offset away from the camera lens. A distance between theshoulder and the apex can be between 10 mm and 30 mm. A diameter of theframe at the shoulder can be between 20 mm and 40 mm. The frame caninclude a tapered tip. An angle of the taper can be between 30° and 60°.The set axial distance can be between 25 mm and 45 mm. The struts of theplurality of struts can be separated by 30° to 120°. There can bebetween 4 and 6 struts in the plurality of struts. Each of the pluralityof struts can be self-expandable. Each of the plurality of struts can beformed of a shape memory material. The frame can include a biodegradableportion.

In general, in one embodiment, a method of enhancing visualization of abody lumen includes: (1) positioning a device including a capsuleendoscope and a plurality of struts attached thereto into a body lumen;(2) expanding the plurality of struts of the device within the bodylumen such that the plurality of struts extend both radially and axiallyaway from a camera lens of the capsule endoscope and meet at an apexthat is positioned a set axial distance away from the camera lens; and(3) imaging with the camera lens into the body lumen.

This and other embodiments can include one or more of the followingfeatures. The plurality of struts can form a frame around the cameralens upon expansion. The frame can include a shoulder that is positioneda maximum radial distance away from the capsule endoscope. The shouldercan be axially offset away from the camera lens. A distance between theshoulder and the apex can be between 10 mm and 30 mm. A diameter of theframe at the shoulder can be between 20 mm and 40 mm. The plurality ofstruts can form a frame around the camera lens upon expansion. The framecan include a tapered tip. An angle of the taper can be between 30° and60°. The set axial distance can be between 25 mm and 45 mm. The strutsof the plurality of struts can be separated by 30° to 120° uponexpansion. There can be between 4 and 6 struts in the plurality ofstruts. Expanding the plurality of struts can include self-expanding theplurality of struts. Each of the plurality of struts can be formed of ashape memory material. The plurality of struts can form a frame aroundthe camera lens upon expansion. The method can further includedissolving at least a portion of the frame to allow passage of thedevice from the body.

In general, in one embodiment, a device for distending a body lumen forenhanced visualization with a capsule endoscope that includes a cameralens includes an attachment element configured to attach to the capsuleendoscope and a plurality of struts fixed to the attachment element. Theplurality of struts are configured to self-expand from a constrainedconfiguration to an expanded configuration in which the plurality ofstruts extend both axially and radially away from the camera lens so asto form a frame therearound.

This and other embodiments can include one or more of the followingfeatures. The struts can be configured to self-expand based upon atrigger within the body lumen. The attachment element can be an annularring. The attachment element can be configured to attach to the capsuleendoscope through friction fit, adhesive, or clamping. The frame caninclude a tapered tip. An angle of the taper can be between 30° and 60°.The struts of the plurality of struts can be separated by 30° to 120° inthe expanded configuration. There can be between 4 and 6 struts in theplurality of struts. Each of the plurality of struts can be formed of ashape memory material. The frame can include a biodegradable portion.

In general, in one embodiment, a device for visualization of a bodylumen includes a capsule endoscope with a camera lens and a plurality ofstruts attached to the capsule endoscope. The plurality of struts areconfigured to self-expand from a constrained configuration to anexpanded configuration in which the plurality of struts extend bothaxially and radially away from the camera lens so as to form a frametherearound.

This and other embodiments can include one or more of the followingfeatures. The device can further include a covering around the strutsconfigured to hold the plurality of struts in the constrainedconfiguration. The covering can be configured to dissolve in the bodylumen. The struts can be configured to self-expand based upon a triggerwithin the body lumen. The frame can include a tapered tip. An angle ofthe taper can be between 30° and 60°. The struts of the plurality ofstruts can be separated by 30° to 120° in the expanded configuration.There can be between 4 and 6 struts in the plurality of struts. Each ofthe plurality of struts can be formed of a shape memory material. Theframe can include a biodegradable portion.

In general, in one embodiment, a method of enhancing visualization of abody lumen includes: (1) positioning a device including a capsuleendoscope and a plurality of struts attached thereto into a body lumen;(2) self-expanding the plurality of struts of the device within the bodylumen from a constrained configuration to an expanded configuration inwhich the plurality of struts extend both radially and axially away froma camera lens of the capsule endoscope; and (3) imaging with the cameralens through the frame into the body lumen.

This and other embodiments can include one or more of the followingfeatures. The frame can include a tapered tip. An angle of the taper canbe between 30° and 60°. The struts of the plurality of struts can beseparated by 30° to 120° in the expanded configuration. There can bebetween 4 and 6 struts in the plurality of struts. Each of the pluralityof struts can be formed of a shape memory material. The plurality ofstruts can form a frame around the camera lens in the expandedconfiguration. The method can further include dissolving at least aportion of the frame to allow passage of the device from the body.

In general, in one embodiment, a device for distending a body lumen forenhanced visualization with a capsule endoscope that includes a cameralens includes an attachment element configured to attach to the capsuleendoscope and a plurality of struts fixed to the attachment element. Theplurality of struts are configured to extend both axially and radiallyaway from the camera lens so as to form a frame therearound. The framefurther includes one or more biodegradable portions.

This and other embodiments can include one or more of the followingfeatures. The one or more biodegradable portions can include a nodebetween struts. The plurality of struts can include rounded ends uponbiodegradation of the node. The one or more biodegradable portions caninclude a node within a strut. The frame can include a tapered tip. Anangle of the taper can be between 30° and 60°. The struts of theplurality of struts can be separated by 30° to 120°. There can bebetween 4 and 6 struts in the plurality of struts. Each of the pluralityof struts can be self-expandable. Each of the plurality of struts can beformed of a shape memory material. The attachment element can be anannular ring. The attachment element can be configured to attach to thecapsule endoscope through friction fit, adhesive, or clamping.

In general, in one embodiment, a device for visualization of a bodylumen includes a capsule endoscope with a camera lens and a plurality ofstruts attached to the capsule endoscope. The plurality of struts areconfigured to extend both axially and radially away from the camera lensso as to form a frame therearound. The frame further includes one ormore biodegradable portions.

This and other embodiments can include one or more of the followingfeatures. The one or more biodegradable portions can include a nodebetween struts. Each of the plurality of struts can include rounded endsupon biodegradation of the node. The one or more biodegradable portionscan include a node within a strut. The frame can include a tapered tip.An angle of the taper can be between 30° and 60°. The struts of theplurality of struts can be separated by 30° to 120°. There can bebetween 4 and 6 struts in the plurality of struts. Each of the pluralityof struts can be self-expandable. Each of the plurality of struts can beformed of a shape memory material.

In general, in one embodiment, a method of enhancing visualization of abody lumen includes (1) positioning a device including a capsuleendoscope and a plurality of struts attached thereto into a body lumen;(2) expanding the plurality of struts of the device within the bodylumen such that the plurality of struts extend both radially and axiallyaway from a camera lens of the capsule endoscope to form a frametherearound; (3) imaging with the camera lens through the frame into thebody lumen; and (4) dissolving at least a portion of the frame to allowpassage of the device from the body lumen.

This and other embodiments can include one or more of the followingfeatures. The frame can include a tapered tip. An angle of the taper canbe between 30° and 60°. The struts of the plurality of struts can beseparated by 30° to 120° upon expansion. There can be between 4 and 6struts in the plurality of struts. Each of the plurality of struts canbe formed of a shape memory material. The method can further includedissolving at least a portion of the frame to allow passage of thedevice from the body. The portion of the frame can include a nodebetween struts. The plurality of struts can include rounded ends uponbiodegradation of the node. The portion of the frame can include a nodewithin a strut.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe claims that follow. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIGS. 1A-1E show the intestine at various stages of insufflation.

FIGS. 2A-2D are schematics showing exemplary instances in which thefield of view with a capsule endoscope can be obscured.

FIG. 3 shows a capsule endoscope with an exemplary luminal expansiondevice projecting from the proximal and distal ends.

FIG. 4 shows a capsule endoscope with an exemplary luminal expansiondevice projecting from the distal end.

FIGS. 5A-5B show dimensions of an exemplary luminal expansion device.

FIG. 6 shows an exemplary rounded luminal expansion device.

FIG. 7 shows a luminal expansion device including an inflatable element.

FIG. 8 shows a spiral luminal expansion device.

FIG. 9 shows a luminal expansion device including an injection moldeddome with struts.

FIG. 10 shows an injection molded luminal expansion device with aplurality of apertures therein.

FIG. 11 shows an injection molded luminal expansion device with domes onthe proximal and distal ends.

FIG. 12 shows a luminal expansion device in a rounded dome shape with alow curvature.

FIG. 13 shows a luminal expansion device in a rounded dome shape with amedium curvature.

FIG. 14 shows a luminal expansion device in a rounded dome shape with ahigh curvature.

FIG. 15 shows a luminal expansion device with struts spiraled away fromthe attachment mechanism.

FIG. 16 shows another luminal expansion device with struts spiraled awayfrom the attachment mechanism.

FIG. 17 shows a luminal expansion device including a cylindrical cagewith a tapered tip.

FIG. 18 shows a spherical luminal expansion device.

FIG. 19 shows a disk shaped luminal expansion device.

FIG. 20 shows a spiral luminal expansion device.

FIG. 21 shows a luminal expansion device attached to the end of acatheter endoscope.

FIGS. 22A-C show an exemplary luminal expansion device for aside-viewing capsule endoscope.

FIG. 23A shows use of a tube to collapse a luminal expansion device.

FIG. 23B shows a capsule over a collapsed luminal expansion device.

FIG. 24 shows a loop of a luminal expansion device.

FIG. 25A shows a luminal expansion device with biodegradable nodes.

FIG. 25B shows a separated portion of the luminal expansion device ofFIG. 25A.

FIGS. 26A-26B shows struts that have been dissolved from a luminalexpansion device.

FIG. 27 shows exemplary decay rates of different nodes of a luminalexpansion device.

FIG. 28 shows use of a luminal expansion device inside thegastrointestinal tract.

FIG. 29 shows a luminal expansion device with a tug used inside of thegastrointestinal tract.

FIG. 30A shows an image gathered from a capsule endoscope inside a lumenwhen a luminal expansion device is used.

FIG. 30B shows an image gathered from a capsule endoscope inside a lumenwhen a luminal expansion device is not used.

DETAILED DESCRIPTION

Described herein are devices for use with a capsule endoscope (CE) (apill camera, pillcam, wireless capsule endoscope, or video capsuleendoscope (VCE)) that significantly aid in more complete luminalvisualization during capsule endoscopy. The devices create localdistension of gastrointestinal luminal tissue away from the camera,improving diagnostic yield.

An exemplary luminal expansion device 300 is shown in FIG. 3. The device300 includes a central attachment mechanism 303 configured to attach tothe capsule endoscope 305. For example, the attachment mechanism 303 canbe an annular ring. Further, the attachment mechanism 303 can beconfigured to attach by friction fit, adhesive, clamp, or otherattachment mechanism to or around the capsule endoscope 305. Theattachment mechanism 303 can be positioned, for example, around thecentral portion and/or end of the capsule endoscope 305 while stillmaintaining a clear lens.

A plurality of radiating struts 301 extend from the attachment mechanism303. The struts 301 emerge from the attachment mechanism 303 (and thusthe capsule endoscope 305), extending both axially and radially outwardfrom the camera lens. In other words, the struts 301 are positioned awayfrom the end of the capsule endoscope 305 along the axis 399 (orparallel to the axis 399). The struts 301 also extend radially away fromthe central axis 399. The struts 301 can each form a shoulder 336 thatis radially offset from the camera lens (i.e., to hold tissue away fromthe sides of the lens of the capsule endoscope 305). The shoulder 336can be positioned at the maximum radial distance away from the capsuleendoscope 305. Further, the shoulder 336 can be axially offset away fromthe body of the capsule endoscope 305. Further, the struts 301 can meetor cross at an apex 333, i.e., at a point positioned a maximum axialdistance away from the lens of the capsule endoscope 305. In oneembodiment, and as shown in FIG. 3, the struts 301 can form a loop madeof two continuous struts. The struts 301 can form a frame (e.g., a cage,space frame, wire frame, stent cage, or tenting structure). The framecan be, for example, conical, tapered, or wedge-shaped with the apex 333forming the tip and the struts widening out to the shoulders 336 beforeextending back, and then in towards the capsule endoscope 305.

In use, the struts 301 can be configured to distend tissue (e.g., withinthe small intestine) such that luminal folds are unfolded, enabling morecomplete visualization. The apex 333 can act as the leading edge whilethe wedge or conical shape of the tip can open tissue up as the device300 moves through, maintaining an open field of view for the camera ofthe capsule endoscope 305. The shoulders 336 can help maintain a widefield of view in front of the lens. Moreover, the gaps between thestruts 301 can create apertures that allow direct, unobscured tissueviewing. The primarily open structure of the device 300 can furtherenable the thru-passage of matter, such as chyme, during use.

As shown in FIG. 3, in some embodiments, struts 301 can extend from boththe proximal end and the distal end (e.g., so as to allow for imagingthrough lenses on both the proximal and distal ends). In otherembodiments, as shown in FIG. 4, the device 400 can include struts 401that extend only from a single end of the capsule endoscope 405.

Referring to FIGS. 5A-5B, the expansion device 500 can have struts 501with configurations and dimensions that enable efficient and effectiveexpansion of the lumen. For example, the length L from the apex 533 tothe opposite end of the capsule endoscope 505 (i.e., the length of thedevice 500 plus the endoscope 505 when the device 500 is positioned onthe endoscope 505) can be 35 mm-80 mm, such as 50-70 mm. Further, thelength L2 from the end of the scope 505 to the apex 533 (i.e., the axiallength that the apex 533 extends away from the scope 505) can 10 mm-50mm, such as 25-45 mm. The length L3 (e.g., the length of the taper fromthe shoulder 536 to the apex 533) can be 5 mm-40 mm, such as 10 mm-30mm. The length L4, i.e., the length of the capsule endoscope 505, istypically 24 mm-31 mm, and the diameter D1, i.e., the diameter of thecapsule endoscope 505, is typically 9-13 mm, such as approximately 11mm. The diameter D2 of the device 500 (i.e., from shoulder 536 toshoulder 536) can be 15-65 mm, such as 20-40 mm. Further, the angle ofthe taper A1 (i.e., the angle that a strut 501 makes with thelongitudinal axis of the device 555) can be 30° to 60°, such as 45°.Finally, the angle A2 between neighboring struts 501 can be, forexample, 30 to 120 degrees.

The number of struts in each expansion device, and their contactingareas, can vary. For example, the device can include between 3 and 12struts, such as between 4 and 6 struts, on the distal side and/or theproximal side of the capsule endoscope.

Further, the struts can be spring-like, resilient, or deformable, suchthat they create an expansive outward force, but are also still flexibleenough such that they can be compressed by a sphincter, orifice, orstricture. In some embodiments, for example, the struts can be made ofNitinol wire and can have a diameter, for example, of 0.010 inches to0.020 inches, such as 0.013 inches or 0.016 inches. In anotherembodiments, the struts can be made, for example, of a collagen or PEEKsuture material and can have a diameter, for example, of 0.020 inches to0.060 inches, such as 0.030 inches.

In some embodiments, as with devices 300, 400, 500, the shoulder area(335, 436, 536) can extend substantially parallel to the longitudinalaxis of the device, thereby creating a non-rounded or flattened portionof each strut. In other embodiments, as shown in FIG. 6, the struts 601of the device 600 can be rounded through the shoulder 636. Further, insome embodiments, the struts 601 can be rounded through the apex 633.For example, the device 600 can take on a rounded dome shape. Similarrounded dome-shaped devices are shown in FIGS. 12-14. In FIG. 12, forexample, there are six struts 1201 that extended in a rounded dome shapeand meet at apex 1233. FIG. 13 similarly has four struts 1301 thatextend through rounded shoulders and meet at apex 1333. The struts 1201,1301 of FIGS. 12 and 13 have a fairly low curvature and result in aframe or cage with a fairly low diameter (e.g., with a diameter that isonly 10-30% greater than the diameter of the capsule itself). Incontrast, FIG. 14 shows a device 1400 with struts 1401 that have largercurvature and result in a frame or cage with a fairly high diameter(e.g., with a diameter that is 50%-150% greater than the diameter of thecapsule itself).

Referring to FIG. 15, in some embodiments, the struts 1501 can bespiraled away from the attachment mechanism 1503. That is, while thestruts 1501 meet in an apex 1533, they do not extend in a single planethat is extends through the central longitudinal axis (as in devices300, 400, 500, 600). Rather, each strut 1501 wraps circumferentiallyaround the longitudinal axis of the capsule endoscope 1505 (while stillextending radially outwards and axially away from the attachmentmechanism 1503). FIG. 16 shows a similar device 1600 with struts 1601that both spiral and extend through an apex 1633.

Referring to FIGS. 22A-22C, in some embodiments, the struts 2201 can bepositioned such that the apex 2233 is near or adjacent to the proximaland/or distal end of the capsule endoscope 2205 while the struts areheld or positioned a set radial distance away from the capsule endoscope2205 along substantially the entire length of the scope 2205. In thisconfiguration, the shoulder 2236 is positioned radially away from, andaxially aligned with the capsule endoscope 2205. In such an example, theattachment mechanism between the capsule endoscope 2205 and the struts2201 can be, for example, at the apex 2233. The device 2200 can beadvantageous for a capsule endoscope that has side-viewing cameras (suchside-viewing cameras can utilize multiple cameras configured in anarray, typically each at or near the capsule endoscopes's axial center).

Further, as shown in FIG. 8, in some embodiments, the expansion device800 can include a coiled strut 801 that coils or spirals around theattachment mechanism 803. The coiled strut 801 can be coiled so as toextend away from the attachment mechanism 803. Further, in someembodiments, as shown in FIG. 20, the coiled strut 2001 can taper downat the proximal and/or distal end to aid in navigating through thelumen.

Referring to FIGS. 17-19, in some embodiments, the expansion device caninclude a cage that is made of a plurality of strut elements thatinterconnect at various locations. For example, device 1700 includes aplurality of struts 1701 that meet at a circular ring 1717 in acylindrical shape and then continue on to apex 1733. FIG. 1800 shows adevice 1800 with struts 1801 that cross-over mid-way down the frame toform a substantially spherical shape. Finally, FIG. 19 shows a device1900 with struts 1901 that form a disk-shaped cage.

In some embodiments, the expansion device can be injection molded, suchas an injection-molded polymer (e.g., PEEK, polypropylene, polyethylene,or a high durometer elastomer such as silicone or urethane). Forexample, FIG. 9 shows a device 900 that includes an injection moldeddome that is formed of struts that meet at an apex 933. FIG. 11 shows asimilar injection-molded device 1100 with domes on both the proximal anddistal ends that are made of struts 1101 a,b that meet at an apex 1133a,b. Further, FIG. 10 shows an injection molded device 1000 having aseries of interconnected struts 1001 that form open cells around theperimeter thereof.

In some embodiments, the device can include a central strut withradiating umbrella-like tip elements.

In some embodiments, the expansion device can have a geometry thatenables collapsing for oral entry, as seen in FIG. 23A-B. For example,the device 2300 (which can be any of the devices described herein) canbe folded, bent, rolled-up, spiral wound, or compressed to the collapsedconfiguration. Further, as shown in FIG. 23A, in some embodiments, atube or constricting sheath 2323 can be used to collapse the frame.Moreover, as shown in FIG. 23B, a covering (e.g., a gel-cap covering)2332 can be used to hold the device 2300 in the collapsed configuration.In some embodiments, the covering 2332 can be dissolved in the body,thereby allowing the device to expand into a larger configuration (e.g.,the configurations otherwise shown herein).

The covering 2332 can be formed, for example, of polymers used in thepharmaceutical industry that selectively dissolve in the presence offluids found in different anatomies, including enteric coatings for thedelayed release of orally administered medications (Torpac Inc,Fairfield, N.J.). Other examples include cellulose acetate phthalate(C-A-P, Eastman Chemicals, Kingsport, Tenn.), Eudragit L 100 and S 100(Evonik Industries, Darmstadt, Germany), Acryl-ese (Colorcon, WestPoint, Pa.), and Surelease (Colorcon). In some embodiments, the materialfor the covering 2332 can be chosen to dissolve in the colon (e.g.,Eudragit S 100) or in the small intestine (e.g., other material listedhereinabove). The polymer dissolution profiles of the chosen materialcan be engineered from seconds to weeks, depending on the desiredimaging location. Further, the covering 2332 can be single-coated, ordouble, triple, quadruple, or more coatings.

In some embodiments, the expansion devices described herein can haveintersections (e.g. strut joints) that are fixed, pivot, hinge, slide,or are unattached in order to aid in collapse.

Once the expansion device it is in the stomach or small intestine, thestruts can be expanded. For example, the struts can self-expand due to,e.g., being made of a shape memory material, such as Nitinol.

In some embodiments, expansion can occur once the device is in the smallintestine. In other embodiments, expansion can occur once the device isin the stomach or the colon.

Further, expansion can occur, for example, based upon a trigger,including the chemical environment (e.g., pH since the stomach is moreacidic than the small intestine), moisture, pressure, temperature, orenzymatic activity, time, location, or visual clues (e.g., the cameracan recognize villi, which only occur in the small intestine). In otherembodiments, expansion can occur, for example, based upon a dissolutionmechanism (such as dissolution of the covering described above) ormicro-actuators that are electrically triggered (including the use ofmicro motors, reed switches, magnetic actuators, piezo actuators,nitinol heated by a battery, or a membrane heated by a battery torelease gas, chemicals, or mechanical motion).

Referring to FIGS. 24-26B, in some embodiments, elements of the frameand/or struts can be biodegradable and/or can include biodegradable(bio-decaying or corroding) nodes. The nodes can be placed at the joints(i.e., at the junction between two struts) or can be placed within astrut. The biodegradable elements or nodes can detach, shrink,disintegrate, or dissolve before the device is expelled by the body.When dissolved, the struts and/or strut sub-elements (if the nodes arewithin the strut) can separate from one another to help with expulsion.Such biodegradable materials can include: Magnesium alloys, absorbablesuture materials (including PGA, PLA, PLGA and collagen), PVA plastics(including Aquasol and Monosol), lactose, cellulose-acetate, and a rangeof bio-based plant materials, including cotton, flax, bamboo, jute,hemp, wood, coconut. In some embodiments, the biodegradable elements canbe made of edible material, for example pasta derivatives.

As shown in FIG. 24, a device 2400 can include two struts 2401 a,bconnected together in a loop by node 2424. In some embodiments, the node2424 can be biodegradable to allow the loop to separate into a straightsegment. In other embodiments, the node 2424 can be permanent such thatthe loop itself can pass (e.g., the loop can be configured to biodegradefrom a larger frame structure). As shown in FIG. 25, a device 2500 caninclude six struts 2501 and a plurality of biodegradable nodes 2524. Forexample, nodes 2524 a, 22524 b, and 2524 c can all partially or fullydissolve to create an elongate piece that more easily passes, as shownin FIG. 25B. FIGS. 26A and 26B show additional struts 2601 a,b and nodes2624 a,b that would be the resultant elements after nodal decay.

As shown in FIGS. 25-26B, each node can encase a joint between twostruts or strut segments. Further, the nodes can be spherical or ovoid.In addition, as shown in FIG. 26B, the ends 2626 a,b of each strut 2601at the node can be spherical or otherwise atraumatic so that they do notharm the tissue upon dissolution of the nodes.

In some embodiments, the struts can be pre-shaped such that they coil orotherwise shrink into smaller shapes once they have been separated atbiodegradable joints.

In some embodiments, the expansion device can have components withdifferent dissolution rates. In one example, there can be sub-elementstruts that decompose slowly (e.g. over days or weeks) coupled byfusible nodes that decompose more rapidly (e.g., within 24 hours). Anexemplary chart of dissolution of structures is shown in FIG. 27, wherecurve A signifies a faster decay time, and curve C signifies a slowerdecay time.

In some embodiments, the entire structure of the struts can decompose.

Dissolution of all or portions of the devices described herein can aidin passage through the body.

In some embodiments, the struts or other surfaces of the devicesdescribed herein can have surface features incorporated thereon. Forexample, the struts can have coatings that create either enhanced orlowered frictional values. The surface features in some embodiments canbe very small external protrusions or scales to create a retarding orgrabbing effect.

The expansion devices described herein can be comprised of a materialthat does not readily corrode. The material can be elastic orsuperelastic (e.g., nitinol). The material can be, for example, ahydrocarbon or a plastic, such as nylon, polycarbonate, or polyethylene,or an elastomer, including a silicone, urethane, or pebax. The strutsand other structures of the devices described herein can be heat set,molded, cast, adhered, or otherwise formed.

In some embodiments, the devices described herein can be covered withone or more sheets, including clear sheets. The sheets can be treated sothat they readily repel or attract wet tissue.

In some embodiments, parts of the expansion devices described herein canbe infused with radio-opaque materials to aid in fluoroscopyvisualization.

In some embodiments, the luminal expansion devices described herein canbe symmetrical (i.e., can be created through an axis of rotation). Inother embodiments, the devices can be asymmetric.

In some embodiments, the leading edge or apex of the expansion devicecan be tapered, bullet-nosed, conical, or rounded.

The struts of the devices described herein can have a circular, oval,square, rectangular, or other cross section.

The struts of the devices described herein can be monolithic, i.e., madeof a single material. In other embodiments, the struts can be compositestructures, such as be made of tubes with an outer layer (with its ownproperties and materials) and an inner portion (with its own propertiesand materials). In one embodiment, the struts can be small tubes thatare inflated with a pressurized fluid or gas.

In some embodiments, referring to FIG. 7, the devices described hereincan include an inflatable element 777, such as a balloon, configuredhold the tissue away from the capsule. The inflatable element 777 can beused in addition to or in place of the cage and strut elements describedherein.

The expansion devices described herein can attach to the housing of thecapsule endoscope or to the optical hood of the capsule endoscope. Insome embodiments, the expansion device can be designed as an integralpart of the capsule endoscope.

Referring to FIG. 28, an expansion device 2800 as described herein canadvance like other swallowed capsule endoscope devices, i.e., thruGI-tract contractions, including peristalsis. The device may not retardspeed-of-passage, but instead it can enhance speed-of-passage, in effectserving to ‘super-trigger’ peristalsis, including through enhanced area,length, and contact points. The device can thus be used to image, forexample, the small intestine or the colon.

Further, referring to FIG. 29, in some embodiments, a small tug element2929 can be attached to the struts 2901 with a tensile member 2930. Thesmall tug element 2929 can thus easily pass through the pylorus and, asit is propelled, pull the struts 2901 and attached capsule endoscope2905 through the pylorus and into the duodenum.

Alternatively, in some embodiments, the expansion device (and capsuleendoscope) can be directly placed into the stomach with an ancillarydevice.

The expansion devices described herein can advantageously improve thefield of view when used with a capsule endoscope. FIG. 30A shows animage gathered of a small intestine with a capsule endoscope when anexpansion device is used while FIG. 30B shows the image gatheredwithout. As shown in FIG. 30B, tissue covers the lens when the expansiondevice is not used, thereby making it difficult to visualize within thesmall intestine. In contrast, when the expansion device is used (FIG.30A), the expansion device holds the tissue away from the camera,allowing better visualization of the lumen. Because both the length andthe diameter of the expansion devices described herein are larger thatof the capsule endoscope itself, the devices can help keep tissue awayfrom the capsule endoscope and create better alignment with the centralaxis of the lumen, thereby creating a passage that is more lumen-centricand improving image quality.

As shown in FIG. 21, in some embodiments, rather than attaching to acapsule endoscope, the expansion device 2100 can be attached to the tipof an endoscope, such as a colonoscope. The expansion device 2100 canhave similar elements (e.g., struts) to any of the expansion devicesdescribed elsewhere herein.

Any of the features or elements of any of the expansion devicesdescribed herein may be combined or substituted for features or elementsof any other expansion device.

Additional details pertinent to the present invention, includingmaterials and manufacturing techniques, may be employed as within thelevel of those with skill in the relevant art. The same may hold truewith respect to method-based aspects of the invention in terms ofadditional acts commonly or logically employed. Also, it is contemplatedthat any optional feature of the inventive variations described may beset forth and claimed independently, or in combination with any one ormore of the features described herein. Likewise, reference to a singularitem, includes the possibility that there are a plurality of the sameitems present. More specifically, as used herein and in the appendedclaims, the singular forms “a,” “and,” “said,” and “the” include pluralreferents unless the context clearly dictates otherwise. It is furthernoted that the claims may be drafted to exclude any optional element. Assuch, this statement is intended to serve as antecedent basis for use ofsuch exclusive terminology as “solely,” “only” and the like inconnection with the recitation of claim elements, or use of a “negative”limitation. Unless defined otherwise herein, all technical andscientific terms used herein have the same meaning as commonlyunderstood by one of ordinary skill in the art to which this inventionbelongs. The breadth of the present invention is not to be limited bythe subject specification, but rather only by the plain meaning of theclaim terms employed.

When a feature or element is herein referred to as being “on” anotherfeature or element, it can be directly on the other feature or elementor intervening features and/or elements may also be present. Incontrast, when a feature or element is referred to as being “directlyon” another feature or element, there are no intervening features orelements present. It will also be understood that, when a feature orelement is referred to as being “connected”, “attached” or “coupled” toanother feature or element, it can be directly connected, attached orcoupled to the other feature or element or intervening features orelements may be present. In contrast, when a feature or element isreferred to as being “directly connected”, “directly attached” or“directly coupled” to another feature or element, there are nointervening features or elements present. Although described or shownwith respect to one embodiment, the features and elements so describedor shown can apply to other embodiments. It will also be appreciated bythose of skill in the art that references to a structure or feature thatis disposed “adjacent” another feature may have portions that overlap orunderlie the adjacent feature.

Terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention.For example, as used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, steps, operations, elements, components, and/orgroups thereof. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items and may beabbreviated as “/”.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if a device in thefigures is inverted, elements described as “under” or “beneath” otherelements or features would then be oriented “over” the other elements orfeatures. Thus, the exemplary term “under” can encompass both anorientation of over and under. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Similarly, the terms“upwardly”, “downwardly”, “vertical”, “horizontal” and the like are usedherein for the purpose of explanation only unless specifically indicatedotherwise.

Although the terms “first” and “second” may be used herein to describevarious features/elements, these features/elements should not be limitedby these terms, unless the context indicates otherwise. These terms maybe used to distinguish one feature/element from another feature/element.Thus, a first feature/element discussed below can be termed a secondfeature/element, and similarly, a second feature/element discussed belowcan be termed a first feature/element without departing from theteachings of the present invention.

As used herein in the specification and claims, including as used in theexamples and unless otherwise expressly specified, all numbers may beread as if prefaced by the word “about” or “approximately,” even if theterm does not expressly appear. The phrase “about” or “approximately”may be used when describing magnitude and/or position to indicate thatthe value and/or position described is within a reasonable expectedrange of values and/or positions. For example, a numeric value may havea value that is +/−0.1% of the stated value (or range of values), +/−1%of the stated value (or range of values), +/−2% of the stated value (orrange of values), +/−5% of the stated value (or range of values), +/−10%of the stated value (or range of values), etc. Any numerical rangerecited herein is intended to include all sub-ranges subsumed therein.

What is claimed is:
 1. A device for distending a body lumen for enhancedvisualization with a capsule endoscope that includes a camera lens, thedevice comprising: an attachment element configured to attach to thecapsule endoscope; and a plurality of struts extending from theattachment element and meeting at an apex, wherein the plurality ofstruts are configured to extend both axially and radially away from thecamera lens so as to form a frame therearound with the apex positioned aset axial distance away from the camera lens.
 2. The device of claim 1,wherein the attachment element is an annular ring.
 3. (canceled)
 4. Thedevice of claim 1, wherein the frame includes a shoulder that ispositioned a maximum radial distance away from the capsule scope.
 5. Thedevice of claim 4, wherein the shoulder is axially offset away from thecamera lens. 6-11. (canceled)
 12. The device of claim 1, wherein thereare between 4 and 6 struts in the plurality of struts.
 13. The device ofclaim 1, wherein each of the plurality of struts is self-expandable. 14.The device of claim 13, wherein each of the plurality of struts isformed of a shape memory material.
 15. The device of claim 1, whereinthe frame includes a biodegradable portion.
 16. A device forvisualization of a body lumen, comprising: a capsule endoscope includinga camera lens; a plurality of struts extending from the capsuleendoscope and meeting at an apex, wherein the plurality of struts extendboth axially and radially away from the camera lens so as to form aframe therearound with the apex positioned a set axial distance awayfrom the camera lens.
 17. The device of claim 16, wherein the frameincludes a shoulder that is positioned a maximum radial distance awayfrom the capsule endoscope. 18-24. (canceled)
 25. The device of claim16, wherein there are between 4 and 6 struts in the plurality of struts.26. The device of claim 16, wherein each of the plurality of struts isself-expandable.
 27. The device of claim 26, wherein each of theplurality of struts is formed of a shape memory material.
 28. The deviceof claim 16, wherein the frame includes a biodegradable portion.
 29. Amethod of enhancing visualization of a body lumen, the methodcomprising: positioning a device including a capsule endoscope and aplurality of struts attached thereto into a body lumen; expanding theplurality of struts of the device within the body lumen such that theplurality of struts extend both radially and axially away from a cameralens of the capsule endoscope and meet at an apex that is positioned aset axial distance away from the camera lens; and imaging with thecamera lens into the body lumen.
 30. The method of claim 29, wherein theplurality of struts form a frame around the camera lens upon expansion,the frame including a shoulder that is positioned a maximum radialdistance away from the capsule endoscope. 31-33. (canceled)
 34. Themethod of claim 29, wherein the plurality of struts form a frame aroundthe camera lens upon expansion, the frame including a tapered tip.35-37. (canceled)
 38. The method of claim 29, wherein there are between4 and 6 struts in the plurality of struts.
 39. The method of claim 29,wherein expanding the plurality of struts comprises self-expanding theplurality of struts.
 40. (canceled)
 41. The method of claim 29, whereinthe plurality of struts form a frame around the camera lens uponexpansion, and wherein the method further comprises dissolving at leasta portion of the frame to allow passage of the device from the body.42-100. (canceled)